After six months of contentious debate over U.S. National Security Agency surveillance programs, prompted by leaks from former government contractor Edward Snowden, the third week in December may have marked a major turning point.

The NSA surveillance and data collection programs—including the bulk collection of U.S. telephone records and surveillance of overseas Internet traffic—have had their strong defenders, including President Barack Obama’s administration and members of congressional intelligence oversight committees.

U.S. intelligence officials continue to insist the programs are legal and necessary, and that there’s no better way to track terrorists than bulk collection of phone records.

But the NSA took two major hits this week. U.S. District Court Judge Richard Leon, in a preliminary ruling in a court case challenging the phone records collection, slammed the agency’s efforts and suggested the program violates the U.S. Constitution’s Fourth Amendment.

Leon’s 68-page opinion amounted to a smack down of the NSA program. “I have little doubt that the author of our Constitution, James Madison, who cautioned us to beware ‘the abridgement of freedom of the people by the gradual and silent encroachments by those in power,’ would be aghast,” he wrote.

Two days later, the White House released a report from the Obama-appointed Review Group on Intelligence and Communications Technology that questioned the need for the collection of bulk telephone records.

Offering no less than 46 recommendations on how to change U.S. government surveillance programs, the report said that the telephone metadata collection program was “not essential to preventing attacks and could readily have been obtained in a timely manner using conventional ... orders.”

U.S. surveillance programs create barriers to international commerce and sour the U.S. government’s relationship with other countries, the report said. “Excessive surveillance and unjustified secrecy can threaten civil liberties, public trust, and the core processes of democratic self-government,” the report said. “All parts of the government, including those that protect our national security, must be subject to the rule of law.”

The review group’s report was more measured than Leon’s opinion, with no overt claim that the NSA programs violate the Fourth Amendment. But the panel also recommended that the phone records data be taken out of the NSA’s hands, and for new restrictions on the ability of the U.S. Foreign Intelligence Surveillance Court to compel telecom carriers and other companies to disclose private information to the government.

Leon’s decision, along with the review group’s report, work together to create a huge change in momentum in the debate, said Greg Nojeim, senior counsel at the Center for Democracy and Technology, a digital rights group that’s been critical of the NSA surveillance.

The review board’s assertion that the NSA phone records program isn’t essential to counterterrorism “pulls the legs out from under” the Obama administration’s claims that the program is necessary, Nojeim said. “It’s devastating.”

In the long term, the review board’s report may be more damaging to the NSA’s current mode of operation than Leon’s ruling. The court case Leon is overseeing in U.S. District Court for the District of Columbia is in its initial stages, with the U.S. Department of Justice likely to appeal.

Leon’s decision seems to conflict with a ruling last month by Judge Jeffrey Miller of the Southern District of California, and it could be many months before the D.C. case is resolved or is sent on to an appeals court or the U.S. Supreme Court, legal experts said.

Meanwhile, it’s unclear what Obama will do with the review boards’ report, with a formal reaction from the White House expected in January. Some news reports have suggested that Obama will reject some of the recommendations. The White House offered little comment on the report following its release.

But several advocates of NSA surveillance reform say the week’s events will put pressure on both Obama and Congress to make changes.

The two big events of the week have “launched forward the momentum” for reasonable surveillance reform, said Lynne Bradley, director of government relations at the American Library Association, a group that’s long pushed for more privacy protections from surveillance.

Still, Bradley predicted, changes in the U.S. surveillance structure could take years, with difficult debates still to come. “We have to prepare for the long haul,” she said. “These [events] are little points of light.”

In addition to Leon’s opinion and the task force report, a group of tech executives met with White House officials during the week to voice their concerns about surveillance.

Also during the week, more than 50 groups and companies wrote to congressional leaders urging them to oppose the FISA Improvements Act, a bill sponsored by Senator Dianne Feinstein, a California Democrat and chairwoman of the Senate Intelligence Committee. Feinstein’s bill would add some transparency to the surveillance process but would largely codify current NSA practices.

The events of the week build on a request in earlier December from eight large Internet firms, including Google, Facebook and Apple, for surveillance reform in the U.S. and other countries.

”At this point, the NSA’s bulk collection program has been roundly and unanimously criticized by privacy and civil liberties advocates, the Internet industry, a bipartisan selection of key Congressional leaders, a federal court, and the president’s own hand-picked panel of advisors,” said Kevin Bankston, policy director of the New America Foundation’s Open Technology Institute, another group critical of the NSA programs. “The tide had definitively turned against the NSA’s mass surveillance practices.”

Bankston, in an email, called on Obama to halt the program as soon as possible. Obama “needn’t wait for Capitol Hill” to act, he said.

U.S. lawmakers have introduced about 20 bills aimed at reforming the NSA surveillance process, with the USA Freedom Act attracting 135 co-sponsors between its two versions in the House of Representatives and the Senate. Many NSA critics are pinning their hopes to that bill, with chief sponsors including Senator Patrick Leahy, a Vermont Democrat and chairman of the Senate Judiciary Committee, and Representative Jim Sensenbrenner, a Wisconsin Republican and author of the 2001 antiterrorism bill, the Patriot Act.

Some defenders of the NSA programs didn’t respond to requests for comments. Attorney Nick Ackerman, who focuses on computer and privacy issues at the Dorsey and Whitney law firm in New York, said he disagrees with Leon’s opinion that the NSA phone records program violates the U.S. Constitution because it doesn’t collect the content of the calls.

Still, following the Obama board’s report, Ackerman expects some changes in the NSA programs.

”NSA may not be the one gathering the records that will remain with the phone companies until needed, but the government will still have the capability to use the information when it can show before the FISA court it has a specific need,” he said in an email. “Forcing the government to be specific in each instance will likely make the program more cost effective and efficient.”

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